Every monitor, every beam, every millisecond — laid out in three dimensions before a single cable is bought. Six stems leave the laptop and take their place in the room.
The layout is the mix. Three decisions define the room — and all three are free, they just have to be made before the first speaker stands up.
All six monitors sit on a single 2.4 m arc around the sweet spot. No stem is closer to your ears than another — air delay is identical for every channel, so the mix arrives coherent. The arc does what no software can.
Ear-height tweeters and a slight toe-in give every monitor the same on-axis response at the listener. Same distance, same angle, same arrival — that's a calibrated room, not a circle of speakers.
The interface owns the clock; the app slaves to it at 48 kHz. Six channels are one multichannel stream — same buffer, same crystal. Cable lengths differ by meters; at electrical speed that's nanoseconds. Irrelevant.
The app hands each stem to its own output on the interface through a zero-copy ring — summed to mono, because the room is the stereo field: a stem's position in space is its pan. Six cables leave the box; six monitors answer. No summing anywhere in the path.
The envelope follower lives inside the audio engine — amplitude, centroid and onsets go straight out a USB-DMX dongle in short 6-channel frames. MIDI stays as an optional tap for the MIDI rig to come.
Same idea, two builds. The naïve stack towers over the tuned one — the tuning isn't magic, it's deleting two monsters: the FFT lookback and the full DMX universe.
A 2048-bin FFT describes the last 42.7 ms of audio — any trigger built on it can only be dated ±21 ms. The worklet watches the waveform itself: 2.7 ms of lookback, fires on the attack slope.
A 512-slot DMX frame takes 22.7 ms to transmit — fine for mood washes, wrong for kick-strobes. Six channels need 0.4–2 ms in short-frame mode. Check this spec on the dongle before buying.
Absolute latency is hardware reality. Relative latency is what the ears judge — and six stems on one clock arrive sample-aligned. That number is zero and can never drift.
The actual recommended hardware, to scale. One interface, six of one monitor model, one dongle, six PARs, one MIDI dongle for the future. Every piece earns its place in the signal path.
Both stages demos in an afternoon. Neither touches the other — sound first, light second, exactly as the layout shows.
Interface + six KRK ROKIT 5s + balanced runs. Place the arc, aim the tweeters, run the ring-buffer build, and hear six stems take their places in the room.
Dongle + six SlimPARs + DMX cable + terminator. Address 1–6, hang the truss, feed the envelope follower, and watch the beat come out of the wall — ~8 ms behind, imperceptible.